Simplify the following expression: $t = \dfrac{8}{5q} - \dfrac{1}{8q}$
Explanation: In order to subtract expressions, they must have a common denominator. The smallest common denominator is the least common multiple of $5q$ and $8q$ $\lcm(5q, 8q) = 40q$ $ t = \dfrac{8}{8} \cdot \dfrac{8}{5q} - \dfrac{5}{5} \cdot \dfrac{1}{8q} $ $t = \dfrac{64}{40q} - \dfrac{5}{40q}$ $t = \dfrac{64 -5}{40q}$ $t = \dfrac{59}{40q}$